add tests for gunzip
[oweals/busybox.git] / libbb / llist.c
index 0d599db6b4974cbce25285b9855c11402b114ec6..4b3971bbe58968b924355217834f450f4c8aa84d 100644 (file)
  * Copyright (C) 2003 Glenn McGrath
  * Copyright (C) 2005 Vladimir Oleynik
  * Copyright (C) 2005 Bernhard Fischer
+ * Copyright (C) 2006 Rob Landley <rob@landley.net>
  *
- * Licensed under the GPL v2, see the file LICENSE in this tarball.
+ * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
  */
-#include <stdlib.h>
+
 #include "libbb.h"
 
-#ifdef L_llist_add_to
 /* Add data to the start of the linked list.  */
-llist_t *llist_add_to(llist_t *old_head, char *new_item)
+void llist_add_to(llist_t **old_head, void *data)
 {
-       llist_t *new_head;
-
-       new_head = xmalloc(sizeof(llist_t));
-       new_head->data = new_item;
-       new_head->link = old_head;
+       llist_t *new_head = xmalloc(sizeof(llist_t));
 
-       return (new_head);
+       new_head->data = data;
+       new_head->link = *old_head;
+       *old_head = new_head;
 }
-#endif
 
-#ifdef L_llist_add_to_end
 /* Add data to the end of the linked list.  */
-llist_t *llist_add_to_end(llist_t *list_head, char *data)
+void llist_add_to_end(llist_t **list_head, void *data)
 {
-       llist_t *new_item;
+       llist_t *new_item = xmalloc(sizeof(llist_t));
 
-       new_item = xmalloc(sizeof(llist_t));
        new_item->data = data;
        new_item->link = NULL;
 
-       if (list_head == NULL) {
-               list_head = new_item;
-       } else {
-               llist_t *tail = list_head;
+       if (!*list_head)
+               *list_head = new_item;
+       else {
+               llist_t *tail = *list_head;
+
                while (tail->link)
                        tail = tail->link;
                tail->link = new_item;
        }
-       return list_head;
 }
-#endif
 
-#ifdef L_llist_pop
 /* Remove first element from the list and return it */
 void *llist_pop(llist_t **head)
 {
-       void *data;
+       void *data, *next;
 
-       if(!*head) data = *head;
-       else {
-               void *next = (*head)->link;
-               data = (*head)->data;
+       if (!*head)
+               return NULL;
+
+       data = (*head)->data;
+       next = (*head)->link;
+       free(*head);
+       *head = next;
+
+       return data;
+}
+
+/* Unlink arbitrary given element from the list */
+void llist_unlink(llist_t **head, llist_t *elm)
+{
+       llist_t *crt;
+
+       if (!(elm && *head))
+               return;
+
+       if (elm == *head) {
                *head = (*head)->link;
-               free(next);
+               return;
        }
 
-       return data;
+       for (crt = *head; crt; crt = crt->link) {
+               if (crt->link == elm) {
+                       crt->link = elm->link;
+                       return;
+               }
+       }
 }
-#endif
 
-#ifdef L_llist_free
 /* Recursively free all elements in the linked list.  If freeit != NULL
  * call it on each datum in the list */
-void llist_free(llist_t *elm, void (*freeit)(void *data))
+void llist_free(llist_t *elm, void (*freeit) (void *data))
 {
        while (elm) {
                void *data = llist_pop(&elm);
-               if (freeit) freeit(data);
+
+               if (freeit)
+                       freeit(data);
+       }
+}
+
+#ifdef UNUSED
+/* Reverse list order. */
+llist_t *llist_rev(llist_t *list)
+{
+       llist_t *rev = NULL;
+
+       while (list) {
+               llist_t *next = list->link;
+
+               list->link = rev;
+               rev = list;
+               list = next;
        }
+       return rev;
 }
 #endif